1. Field of the Invention
The present invention relates to a method of soldering terminal faces of a substrate using molten solder, as well as to a method of manufacturing a solder alloy of at least two solder components.
2. Description of the Related Art
The demands being imposed on the quality and reliability of soldered connections are constantly growing, not the least because of the increasing miniaturization of electronic components and the ever higher integration levels of ICs. Meeting said demands using the known, industrially applicable techniques requires a considerable outlay which is correspondingly reflected in manufacturing costs. Meanwhile, use of the solder paste technique in conjunction with the reflow method has become widespread. Here, in a first process, paste-like solder material is applied onto the terminal faces and, in a second process, the heat needed for the soldering reaction is introduced. In practice, a serious problem which is frequently encountered here is the introduction of the heat quantity needed for the reflow method in such a targeted and metered manner that, on the one hand, a solder application with as homogeneous a structure as possible is formed and, on the other hand, the occurrence of irreparable damage inside the electronic components as a result of overheating is avoided.
Furthermore, with the known reflow method, depending on the level of quality demanded of a soldered connection it is necessary to effect the method in an inert atmosphere, with the result that the costs merely of providing suitable operating equipment are extremely high.
The object of the present invention is to provide a method which enables the production of high-quality and reliable soldered connections with a substantially reduced outlay for equipment and a lower number of process steps and so allows such electronic components to be manufactured at a far lower cost.